Abstract
The image-intensifier digital radiography (I.I.-DR) system for indirect radiography has been newly introduced in gastric cancer mass screenings at our facility and has been in use since April 2006. In the present study, we tried to estimate the effect of I.I.-DR on the accuracy control by comparing the results obtained by means of I.I.-DR with those obtained by means of conventional photofluorography using X-ray roll film (PF) concurrently performed at our facility. A total of 15,705 examinees from April 2006 to March 2007 (the first year) and 37,897 examinees from April 2007 to March 2008 (the second year) underwent a barium study with I.I.-DR. Their recall rates and detection rates for gastric cancer were 8.4% and 0.31% in the first year, and 8.6% and 0.23% in the second year, respectively. The I.I.-DR data appeared to be as good or better compared to those of PF concurrently performed during those periods (185,551 examinees, 8.3% recall and 0.19% cancer detection rates in the first year; 157,061 examinees, 8.2% and 0.21% in the second year, respectively). Furthermore, the I.I.-DR system improved the image characterization and consequently increased the rate of definite diagnosis of early gastric cancer; however, the interpretation of a digital radiogram on a VDT screen took approximately 1.4 times longer than that of PF on an X-ray film viewer. These results indicate that the introduction of the I.I.-DR system for indirect radiography in gastric cancer mass screenings might contribute to the improvement of the accuracy control.
